Rechargeable batteries come in many types. Different batteries using different chemical materials require different methods of recharging. Current battery chargers are designed to be used for only one type of battery. For example, a lithium-ion battery requires a different battery charger than a nickel-cadmium battery. Each battery charger is configured only for one purpose, such as to maintaining a constant voltage, a constant current, or a predetermined charging algorithm that may vary the voltage or current. More sophisticated battery chargers may use a charging algorithm to charge a battery quickly at first, then slow down the rate of charge as the battery nears full charge.